Audi RS7 Headlight Bulb Size

Additional Notes

• The Audi RS7 high beam headlight specifications for 2014-2018 list two distinct bulb sizes depending on whether the vehicle is equipped with a cornering light system, making the presence or absence of that feature the determining factor in bulb selection.
• RS7 vehicles fitted with a cornering light system across the 2014-2018 range take an H7 bulb for the high beam position. The H7 is a single-filament halogen type operating at 12V and 55W, using a PX26d base, and is recognized under ECE standards as well as regulations in the US and Japan.
• RS7 vehicles without a cornering light system across the same 2014-2018 range take an H8 bulb instead. The H8 is also a single-filament halogen type but operates at a notably lower wattage of 35W rather than 55W, runs on 12V, and uses a PGJ19-1 base.
• The base types of the H7 and H8 are physically different. The H7 uses a PX26d base while the H8 uses a PGJ19-1 base, meaning the two bulbs are not interchangeable despite both being single-filament halogen types operating on 12V.
• The wattage difference between the H7 at 55W and the H8 at 35W reflects a meaningful difference in power draw and light output, which corresponds to their separate roles in headlight assemblies designed around different optical configurations.
• Both the H7 and H8 conform to ECE standards, which govern lighting equipment across Europe and much of the world. The H7 carries additional approval in Japan, whereas the H8 approval outside ECE territories extends to the US only.
• Because the cornering light configuration directly determines which bulb size applies, substituting one for the other would result in a physical fitment failure due to the incompatible base types, regardless of voltage compatibility.